The present invention pertains to group call services and more particularly to group call services through a plurality of networks.
Today group call services are provided by specialized networks such as iDEN (integrated digital enhanced network). A group call is one in which the originator selects a person or persons to which he wishes to speak and the target user's phone immediately transmits the words of the originator, without the ringing and answering of typical phone calls. In an alternate embodiment, the group call can be presented to the target for acceptance by the target. Another group call service is referred to as Call-back. This service provides the ability of the target to rejoin or reestablish a group call that has/had been established.
The iDEN system is a “closed system” which offers group call services to those customers who are currently in the iDEN TDMA (time division multiple access) network. Other networks such as code-division multiple access (CDMA), global system mobile (GSM), internet protocol (IP) and 802.11 type networks do not support group call services at the present time. Non-iDEN subscribers may wish to make group calls to the existing customer base of iDEN subscribers and vice-versa or to mixed iDEN and non-iDEN groups.
The users of group call services are typically organized into talk groups. Talk groups usually contain users that share a common mission, such as a work group. Work groups may be put together such that not all the users are uniformly iDEN or non-iDEN. Current dispatch call service systems are unable to facilitate the connection of such diverse users.
Dispatch systems have been provided to alleviate this problem; however, such group call systems involve many limitations including missed calls, poor audio quality, and gaps in speech.
Accordingly, a need exists to provide for group call services for non-iDEN systems and among iDEN users and non-iDEN systems.